Liquid denture cleanser composition and method of application

ABSTRACT

A sprayable liquid denture cleanser composition comprising an aqueous solution of a detergent selected from the group consisting of sulfonated, sulfated and sulfoacetate fatty alcohols, and a chelating agent of the amino carboxylate or organo phosphonate type. The cleanser is preferably dispensed from a mechanical non-aerosol spraying device such that the force of the spray supplements the cleansing effect of the composition. The composition has particular application on the removal of tartar and calculus as well as stains and plaque adhering thereto.

This application is a continuation-in-part of co-pending U.S. Ser. No.684,818, filed Dec. 20, 1984, now abandoned.

The instant invention relates to a liquid cleanser compositioncomprising (a) a detergent selected from the group consisting ofsulfated, sulfonated and sulfoacetate fatty alcohols; (b) a chelatingagent of the amino carboxylate or organo phosphonate type; and (c) about50% to about 94% water. The composition is designed to be delivered tothe surface through a spray pump system or device. The inventivecleansers are particularly useful as denture cleansers.

The denture cleanser prior art has focused on the use of oxidizingagents and bleaching agents in concert to remove visible stain and scaleor plaque buildup. For the most part these compositions have employed avariety of sulfate salts, e.g., bisulfates and monopersulfates, to serveas detergents and oxidizers, as well as alkali metal and alkali earthmetal halides as bleaches. Perborate, carbonate, bicarbonate andphosphate salts were conventionally included to provide effervescenceand activation. These references have focused on making powdered ortableted products which dissolve rapidly and effervesce when placed inwater. These products clean dentures generally in 12-30 minutes orlonger and require constant emersion during this period, followed bybrushing and rinsing with water.

The persulfate and perborate systems of the prior art tend to discolorthe stain on the denture. Tablets made from these ingredients werelimited to small amounts of detergents or surfactants in order toachieve fast dissolution and subsequent cleansing when placed in water.Detergents of the high fatty alcohol type could therefore not beincorporated except in minute quantities, e.g., 1% or less, or poortablet dissolution rates resulted. The use of hypochlorites as bleachingagents discolor denture stain to an even greater extent then thepersulfates and perborates. These chlorinated agents have a more seriousdisadvantage in that they produce an intolerable and unpleasant aftertaste and odor and may adversely discolor denture metal under certainconditions.

Additionally, althouth the prior art powder and tablet systems removesome of the denture stain, they tend to leave an undissolved residuewhich can only be removed mechanically. Consumers usually revert to asoaking and brushing regimen to obtain a thoroughly clean denture. Othertypes of undissolved residue include chewing gum residue and dentureadhesive residue. These residues are particularly difficult to removeeven with a regular brushing regimen since they become imbedded in thedentures or partial dentures. This obviously has adverse effects on thedenture wearer. Even those chewing gums having non-stick properties andspecially formulated for denture wearers become to some extent imbeddedin the denture crevices. Denture wearers generally prefer a strongdenture adhesive to insure proper adhesive of the denture in the mouth.These types of adhesives have the disadvantage of being very difficultto remove and clean from the denture. The use of water in combinationwith denture cleanser pastes tend to spread out rather than remove thechewing gum and adhesive residue and therefore fail to clean them fromthe denture surface. The inventive compositions solve this problem bylossening the chewing gum and adhesive residue such that it can then beremoved with gentile rubbing with the fingers.

More recently a liquid denture cleanser has been disclosed in U.S. Pat.No. 4,511,486. This reference discloses a foam-producing liquidcomposition comprising from about 1 to about 10% by weight of apharmaceutically acceptable surfactant, about 35 to about 70% by weightof ethanol or isopropanol or mixtures thereof, about 0.1 to about 10% byweight of a pharmaceutically acceptable humectant, about 25 to about 60%water and about 0.5% of an adjuvant. The composition must not containmore than 50% water when 42% alcohol is present and vice versa. Thosesurfactants disclosed are sodium lauryl sulfate SLS, sodium dodecylbenzene sulfontates SDBS, polysorbate 80, poloxomer 407 and mixturesthereof. Humectants are selected from the group consisting of glycerin,sorbitol, polyethylene glycol PEG, propylene glycol PG and mixturesthereof. The use of the trisodium salt of ethylene diamine tetraceticacid (EDTA) in an amount of about 0.5% is also disclosed as a usefuladjuvant.

The composition of this reference relay on their high alcohol contentfor cleaning. As described hereinafter, comparative tests between thecomposition of this reference and the instant invention clearlydemonstrate that the compositions of the instant invention aresignificantly better at removing plaque, calculus, tartar and stainsfrom denture tiles, as well as actual dentures.

FIGS. I and II are photographs of stained dentures. These picturesclearly demonstrate the superior cleaning efficacy of the inventiveliquid spray denture compositions over the prior art tabletedcomposition as well as the prior art liquid denture cleanser of U.S.Pat. No. 4,511,486 described above.

The inventive liquid compositions are designed to be dispensed from apump spray bottle. Thus, the viscosity of the compositions should bekept within a range which is atomizable or sprayable. The spray iseffectuated without aerosol ingredients or pressurized means. Thecompositions do not use oxidizing agents or chlorine-containingcompounds and consequently do not suffer from the disadvantagesassociated with these agents, as does the prior art. The liquid cleanseris sprayed onto the denture, allowed to stand for about 20 to about 120seconds and rinsed in tap water. The length of time the cleanser ispermitted to remain on the denture is dictated by the type and intensityof stain. Most food, tobacco and plaque stains, however, are easilyremoved after about 2 minutes of contact with the liquid cleanser. Theinventive compositions are particularly effective at removing thecalculus and tartar buildup. The instant invention has been shown to beeffective in vivo, i.e., on actual dentures, in removing this buildup.If the composition is used regularly, e.g., on a daily basis, verylittle buildup of stubborn calculus or tartar results. When buildup hasoccurred on the denture, longer contact time between the cleanser andthe denture is required. In such a case, even soaking for a short timemight be recommended. The force of the pump spray supplements thecleansing effect of the cleanser. The pump spray force is designed tomaximize the removal of food particles and stain on the denture surface.Thus, a minimum spray force is required such that it provides amechanical cleansing action without a separate brushing step. Themaximum force must be kept within a range which is controllable andconvenient for the user. This is dictated primarily by consumeracceptability and marketing considerations.

An alternative embodiment to delivery via a pump spray device, is theuse of the composition as a soaking solution. In this embodiment, it issuggested that the solution be diluted with water, since it is in aconcentrated form.

More particularly, the instant liquid denture cleansing compositionsconsist essentially of

(a) detergent present in amounts of about 3 to about 18% by weightselected from the group consisting of sulfonate fatty alcohols havingthe formula ROSO₃ M, sulfated fatty alcohols having the formula ROSO₄ M,sulfoacetates having the formula ROCOCH₂ SO₃ M and mixtures thereof,wherein R is C₁₀₋₁₆, M is a water soluble alkali metal or alkaline earthmetal; and

(b) a chelating agent present in amounts of about 3 to about 18% byweight selected from the group consisting of amino carboxylates, organophosphonates and mixtures thereof; and

(c) water present in amounts of about 50 to about 94% by weight.

The detergent is preferably used in the range of about 3 to about 12%and most preferably about 7 to about 10% by weight. As can beappreciated, the precise amounts chosen within these ranges will bedictated by the degree and type of stain present.

Preferred ranges of the chelating agent are from about 3 to about 15% byweight and more preferred about 3% to about 8% by weight.

When used in the preferred embodiment, e.g., the sprayable form, theweight ratio of detergent to chelating agent is about 2:1 to about 1:1.If the liquid concentrate is used alternatively as a soaking solution,the ratio is generally about 1:4 to about 1:2.

The use of sulfated higher fatty alcohols as detergents are well known.Such anionic detergents, however, when mixed with a suitable chelatingagent, have surprisingly provided a highly effective denture cleanserwhich, when applied with the application force of a pump spray, providea more convenient and efficient denture cleanser that the prior artmethods. The user is able to clean his dentures without soaking them, asrequired in the prior art tablet and powder compositions, and withoutscrubbing or brushing, as required by the prior are sprayablecompositions.

It is critical to the invention that the sulfated fatty alcoholdetergent be used in conjunction with the recited chelating agents inaqueous solution. Certain of the useful detergents, e.g., sodium laurylsulfate, when used by themselves and dispensed from a mechanicalspraying device or from an aerosol mixture, produce an intolerableatmospheric condition situation which is harmful to the respiratorytract. Uncontrollable sneezing or coughing and respiratory irritationresults. Such a situation would restrict the use to well ventilated,controlled areas. It has been discovered, quite unexpectedly, that theinventive compositions can be atomized or sprayed without these harmfulside effects, by forming an aqueous mixture of the detergent with theamino carboxylate or organo phosphonate chelating agent. Thiscombination helps alleviate the adverse respiratory and inhalationproblems associated with the detergents and increases the cleaningefficacy of the composition. The weight ratio of detergent to chelatorrecited above has been carefully selected to achieve superior cleaningand to prevent the dispersion of irritating or harmful fumes.

Examples of useful sulfated fatty alcohol detergents are selected fromthe anionic water soluble class. The potassium, sodium and ammoniumsalts of the higher alkyl benzene sulfonates are preferred. Among these,the sodium linear alkyl benezene sulfonates are preferred. Otherexamples include magnesium lauryl sulfate, potassium lauryl sulfate,sodium dodecylbenzene sulfonate, sodium sulfoacetate, sodium myristylsulfate, sodium lauryl sulfate, sodium cetyl sulfate, sodiun tridecylsulfate and sodium-7-ethyl-2-methyl-4-undecyl sulfate. Mixtures of anyand all of these detergents are also useful.

Other anionic detergents may be incorporated into the composition alongwith the above required detergnets. These supplemental detergents may bepresent in amounts of about 1 to about 5%. These additional detergentsinclude compounds such as the oleic acid ester of sodium isethionate,sodium N-cyclohexyl-N-palmitoyl taurate, sodium N-coconut acid-N-methyltaurate, sodium N-methyl-N-oleyl taurate and mixtures thereof.Fluorochemical surfactants, commonly known as fluorads, are also usefuladditives. Examples include those compounds disclosed in British Pat.No. 1,322,548, having the formula: ##STR1## wherein n is an integer from3 to 10, X is bromine or iodine; and Y is a glycol residue having 3 to10 carbons derived, for example, from ethylene glycol or propyleneglycol as a ethyoxylated alcohol having 1 to 10 moles of ethylene orpropylene oxide.

The use of chelating or sequestering agents in the prior art wastypically in combination with denture cleanser tablets containingperoxygen bleaching agents. The tetrasodium salt of ethylenediaminetetracetic acid (Na₄ EDTA), among others, was commonly used to sequesterthe heavy metal impurities present in solution and prevent thedecomposition of the bleaching agent.

Typically, denture cleansing tablets or powders have used chelatingagents such as Na₄ EDTA in amounts of about 0.5%. More recently adenture tablet composition was described in U.S. Pat. No. 4,540,504 toEoga, whereby from about 10 to about 50% by weight of chelator ispresent. These prior art references are solid tablet compositions,however, not solutions as in the instant invention. Thus, when thetablets are dissolved in water, and the relative amounts of ingredientsare based on the weight of the solution, the chelator range is verysmall. For example, if the chelator range of tablet of theabove-mentioned U.S. Pat. No. 4,540,504 patent is measured based on aweight of the solution it forms when dropped in 125 ml of water, therange is from about 0.16% to about 0.8% by weight. If a typicalcommercial tablet containing 0.5% Na₄ EDTA is dissolved in 125 ml ofwater, the chelating concentration based on the then formed solution is0.012%. These amounts are much smaller than Applicant's range of about 3to about 18% by weight.

Additional useful amino carboxylate chelators include tetrasodiumethylenediaminetetraacetate dihydrate, trisodiumethylenediaminetetraacetate, diammonium ethylenediaminetetraacetate,disodium ethylenediaminetetracetate dihydrate, trisodiumN-hydroxyethylenediaminetriacetate hydrate trisodium nitrilotriacetatemonohydrate, pentasodium diethylenetriaminepentaacetate, trisodiumethylenediaminetetraacetate trihydrate and mixtures thereof. Thesechelators, as well as other well known amino carboyxlates are generallyused within the above-cited ranges in amounts sufficient to contributeto removal of calculus, tartar and any stain and plaque containedthereon.

Those organic phosphonates useful may be selected from a wide range ofconventional materials. Examples include 1-hydroxy-1,1-diphosphonic acidand its sodium, potassium and ammonium salts. These salts are also soldunder the tradename Dequest by Monsanto Company. In addition to beingchelating agents, the organic phosphonates serve as detergent builders.These chelating agents are employed in the same amounts as the aminocarboxylates. Mixtures of any and all of the chelators is alsocontemplated.

The inventive liquid denture cleansers can optionally contain detergentbuilders which are conventionally used in detergent formulations andwhich enhance cleaning and contribute to a brighter surface appearanceof the denture. Useful builders include the water-soluble phosphates,pyrophosphates, ortho phosphates, carbonates and the like. Specificexamples of inorganic phosphate builders useful include the sodium orpotassium salts of tripolyphosphates, pyrophosphates andhexametaphosphates. These builders may also contribute to cleaning. Asmentioned above, the organic phosphonate chelating agents also serve asbuilders. When incorporated into the composition, builders are generallypresent in amounts of about 3% to about 12%; and preferably in amountsof about 5% to about 10%.

Other conventional additives such as flavorings, colorants, perfumes,antimicrobials, preservatives, and the like may be optionallyincorporated in the inventive compositions. For example, flavorings suchas mint, oil of clove, artificial vanilla, to name a few, are useful.These materials may be blended in various combinations and the amountsmay be varied according to the perception desired.

In the instance where colorants are used, F.D. & C. and D. & C. dyes maybe used. Lakes are generally not useful due to their insolubility in theinventive compositions. Those dyes useful are certified by the FederalFood & Drug Administration as acceptable for use in food, drug andcosmetic applications and in drug and cosmetic colorings. The materialsacceptable for the foregoing are preferably water-soluble and includeF.D. & C. Blue No. 2 (indigo dye), F.D. & C. Green No. 1 and 3, to namea few. Conventional preservatives such as methyl and propyl paraben andmixtures thereof may be incorporated in amounts well known in the art.

As previously mentioned, the inventive liquid denture, cleansercompositions are designed to be applied to the denture surface from amechanical spraying device. Simple hand spray pump bottles capable ofdisposing high viscosity fluids are sufficient. Aerosols, includingpiston-driven types, are also useful, but are not preferred since theyare more costly and do not afford any advantages over the mechanicaldevices for purposes of this invention. Application by spraying impartsa certain mechanical cleaning force as the liquid hits the denturesurface. By directing the spraying parameters, e.g., the spray pattern,the weight of liquid applied and the speed of the spray, the cleaningforce can be controlled.

In measuring the force, one fluid once propylene cylindrical pumpbottles having a high viscosity spray dispensing head were filled withthe inventive compositions. The denture or other target was heldstationery in an Instron tensile testing machine. The spray bottle wasmounted horizontally above the target with the spray nozzle at adistance of 1" (2.54 cm) away. An air driven piston/solenoid device wasused to actuate the spray pump. The air pressure driving the piston wasapproximately 5 psi (0.35 kg/cm²). The peak force of the spray againstthe target was recorded by a microprocessor connected to the Instronload cell's output. The measurement was in gram force units. The resultsindicated that a gram force of at least 1 and preferably between about 1to 3 is required to provide enough mechanical action to supplement thecleaning effect of the composition itself.

The weight of the liquid dispensed per actuation of the mechanicalspraying device was measured by subtracting the weight of the liquid andspray bottle after dispensation with the weight prior to dispensation.

The average weight delivered per actuation is about 90 to about 200 mgof liquid; and preferably about 100 to about 150 mg±25 mg of liquid.These amounts are preferred for adequate cleaning of most stains andplaque.

The spray pattern was determined by stationing the spray pump bottle anddirecting the spray nozzle onto an absorbant pad situated about 2" (5cm) away. The pump sprayer was actuated once and the vertical andhorizontal diameters of the spray pattern were measured as they appearedon the pad. The spray pattern is preferably about 1.5" (3.81 cm) toabout 2.5" (6.35 cm) by 1.5" (3.81 cm) to about 2.5" (6.35 cm) at adistance of about 2" (5 cm) from the target. Most preferably, the spraypattern is about 1.85" (4.6 cm)±0.65" (1.65 cm)×1.85 (4.6 cm)±0.65"(1.65 cm) at the 2" (5 cm) distance from the target.

The above measurements were taken to obtain the minimum parametersrelated to the mechanical force required to achieve cleaning. While thecomposition itself is a good cleanser, surprisingly improved cleaning ofthe denture is achieved when the composition is sprayed with sufficientmechanical force to help remove stain, plaque and other debris.

Additional considerations must be given to the choice ofdetergent/chelator formulation such that the formation of undesirableprecipitates is minimized and to prevent the liquid's viscosity frombecoming so high that dispensing from a spray bottle is difficult. Forexample, when ethylenediamine tetracetic tetrasodium salt is used inconjunction with sodium lauryl sulfoacetate (Lanthanol LAL) or anotherlinear alkyl sulfonates, the detergent tends to salt out, forming aninsoluble precipitate and resulting in a thick unsprayable mass.Additionally, the cleansing efficacy of the composition is deleteriouslyaffected when such precipitates form. Thus, it is important that thechelators be readily water-soluble and that the combination of thechelator and detergent result in a solution whose viscosity is readilyand easily dispensed from a mechanical spraying device, and whosestability is maintained during storage. The viscosity problems and thesalting-out effect generally occur at concentrations of chelator above5% and at temperatures below room temperature. Once the insolubleprecipitate is formed it is very difficult to reverse. To help alleviatethese problems, agents which depress the freezing point and prevent theformation of insoluble precipitate can be added. Water soluble,not-toxic glycols, such as polyethylene glycols, in an amount sufficientto prevent an insoluble precipitate from forming are particularly usefulin addressing this problem. The addition of these materials in amountsof from about 1 to about 10% by weight help maintain a stable liquidsolution during storage or shelf-life. Examples of preferredpolyethylene glycols are those having an average molecular weight rangeof about 200 to about 600. These materials are sold under the tradenameCarbowax by Union Carbide, Danbury, CT. Other non-toxic, water-solublederivations of the polyethylene glycols, e.g., alkoxy or etherderivatives are also contemplated.

The term "denture" as used herein, includes artificial teeth, removableorthodontic bridges, dentures, plates and the like.

A high degree of cleansing is generally achieved in less than 1 minuteand preferably in 30 seconds or less. The cleansers, with the aid of themechanical force exerted by the spray, strip off calculus, tartar andplaque, remove mucous resulting from the depositions of proteins andglycoproteins, remove food particles and debris, remove and/or killbacteria, remove residual denture adhesives and chewing gum, and removefood stains and tobacco stains as well as coffee and tea stains. Thesecompositions have been shown to effectively loosen chewing gum anddenture adhesive such that these residues can be easily removed bygently rubbing with the fingers or gentle brushing. These cleansingeffects are achieved without adversely affecting the metal, plastic orother materials of the denture construction.

The instant invention allows the denture wearer to clean his denturesquickly, conveniently in a portable package without the need for acontainer for soaking.

A fuller understanding of the present invention will be gained from thefollowing illustrative examples. Unless specified otherwise all amountsexpressed as percent are intended to be a percent by weight of the totalcomposition.

EXAMPLE ONE

Denture Cleanser compositions were prepared using the formulationstabulated below. Compositions A and B represent preferred embodiments ofthe inventive liquid denture spray composition. Compositions C and Drepresent commercially available denture tablets.

    ______________________________________                                                    Composition                                                                                       C      D                                                    A        B        (Prior/                                                                              (Prior/                                              Inventive                                                                              Inventive                                                                              art    art                                    Ingredients   (Liquid) (Liquid) tablet)                                                                              tablet)                                ______________________________________                                        Sodium Dodecyl                                                                              --       10       --     --                                     Benzene Sulfonate                                                             Sodium Lauryl Sulfate                                                                       10%      --       --     --                                     Ethylenediaminetetra-                                                                        5%      5        3.4     1.25                                  acetic Acid Tetra-                                                            sodium Salt                                                                   Polyethylene Glycol                                                                         --       4        --     --                                     Flavor, color, pre-                                                                          0.5%     0.5     --     --                                     servative                                                                     Water         85.5%    80.5     --     --                                     Sodium Bicarbonate                                                                          --       --       --     14.0                                   Citric Acid   --       --       --     10.3                                   Sodium Carbonate                                                                            --       --       --     12.8                                   Colorant      --       --       0.2    0.1                                    Oxone         --       --       --     39.5                                   Flavor and Fragrance                                                                        --       --       0.5    1.0                                    Detergent     --       --       0.5     0.65                                  Magnesium Stearate                     0.2                                    Sodium Perborate                                                                            --       --       37.3*  12.5                                   Monohydrate                                                                   Anhydrous Sodium                                                                            --       --        22.85*                                                                              --                                     Perborate                                                                     Trisodium Phosphate                                                                         --       --       33.8   --                                     Sodium Benzoate                                                                             --       --       1.0    1.6                                    Polytetrafluoroethylene                                                                     --       --        0.45  --                                     Filler        --       --       --     6.1                                    ______________________________________                                         *Includes approximately 0.45% by weight of total perborate                    polytetrafluoroethylene prepared as a granulated mixture.                

In vitro denture tiles were prepared with plague, a composite of foodstain consisting of grapes, blueberry, tea and coffee as well as tobaccostain.

Samples of the tiles were then chosen to be cleansed with one of thethree compositions listed above. The treatment with Compositions A & B(inventive) were accomplished by spraying the tiles and allowing thespray to remain on each tile type for 30, 60 and 120 seconds prior torinsing with water at 45° C. for 20 seconds.

The treatment with the tablets of Composition C and D (prior art) wasaccomplished by dropping the tablets in beakers of 45° C. watercontaining the tiles. Those tiles treated with Composition C wereallowed to soak for 5 minutes. Those tiles treated with Composition Dwere allowed to soak for 12 minutes.

The results showed that tiles cleaned by the inventive Compositions Aand B for 120 seconds were significantly cleaner than those cleaned withComposition C and D.

Those denture tiles which were cleaned with the inventive Compositions Aand B for 30 and 60 seconds required an additional spraying and animmediate rinsing in order to achieve similar results to the 120 secondtreatment.

Those tiles which had 24 hours plaque accumulated on them were sprayedwith Compositions A and B and allowed to stand for 12 minutes.Additional plaque tiles were soaked in Compositions C and D for 5 and 12minutes respectfully. All the tiles were then rinsed under running waterat 45° C. for 20 seconds and immersed in a basic 0.01% Fuchsin solution.The Fuchsin solution is used as a color indicator for plaque andcalculus. The tiles were the rinsed again ad qualitatively compared forred color. The tiles cleaned with Compositions A & B (inventive) had theleast amount of red color resulting from the Fuchsin, and consequentlythe least amount of plaque.

EXAMPLE TWO

This example is intended to show a comparison between the cleansingefficacy of inventive compositions as compared to a well knowncommercial tablet of the prior art and the liquid foaming denturecleanser disclosed in U.S. Pat. No. 4,511,486) Composition C.

A set of tiles (Set I) were prepared with coffee, tea, blueberry andgrape stains. Another set (Set II) of tiles were prepared havingtobacco, coffee, tea, blueberry and grape on a plaque matrix.

FIG. I shows the results of the food stained tiles after cleaning witheach of the denture cleansers. "Prior Art I," as labeled in the Figures,is the commercial tableted denture cleanser (Composition D, ExampleOne), which was dissolved in a beaker of water (45° C.) containing thetile and left for 12 minutes.

The "Inventive Composition," as labeled in the Figures, is formulation Aset forth in Example 1. The spray was left on the tile for 120 secondsand rinsed with water for 20 seconds at 45° C.

"Prior Art II," as labeled in the Figures, is the liquid foamingComposition C set forth in U.S. Pat. No. 4,511,486. The chelator EDTAhas been added for the sake of comparison to the instant inventivecompositions. This composition had the following formula:

    ______________________________________                                        Sodium dodecyl benzene sulfonate                                                                        3%                                                  Polysorbate 80            1%                                                  Glycerin                  1.5%                                                PEG 400                   0.5%                                                Ethyl alcohol             55%                                                 Water                     36.75%                                              Flavor/color              1.75%                                               EDTA                      0.5%                                                ______________________________________                                    

From observing the photographs in FIGS. I and II, the cleaner (whiter)surfaces are those cleansed with the inventive compositions. Those tilescleaned with the compositon of U.S. Pat. No. 4,511,486 did not becomeclean and therefore exhibit a dark color. These pictures were takenunder identical conditions, and accurately reflect the actual appearanceafter cleaning. It is apparent that the inventive liquid spray denturecleanser compositions exhibited significantly better cleaning than theprior art tableted denture cleanser and the prior art liquid denturecleansers.

EXAMPLE THREE

Further tests were conducted for the purpose of comparing inventiveliquid denture spray composition with those compositions disclosed inU.S. Pat. No. 4,511,486, particularly with respect to their abilities toclean visible tartar and calculus deposits without brushing.Additionally, a preliminary experiment was conducted for the purpose ofcomparing the respective abilities of the compositions to dissolvehydroxyapatite, the main ingredient found in tartar and calculusdeposits. Hydroxyapatite is a major type of calcium phosphateresponsible for calculus and tartar deposits. (Schroeder, H.E.,Formation & Inhibition of Dental Calculus, Hans Huber Publishers, p117-119, 1969).

Five denture cleaning solutions were prepared in accordance with thefollowing compositions:

    ______________________________________                                                 Inventive                                                                            (U.S. Pat. No. 4,511,486)                                                                      Control                                      Ingredient                                                                              A         B      C    D    E    F                                   ______________________________________                                        Sodium Lauryl                                                                           10.0      5.0    5.0  5.0  5.0  --                                  Sulfate                                                                       Na.sub.4 EDTA                                                                           5.0       --     --   --   --   --                                  Na.sub.3 EDTA                                                                           --        0.5    0.5  --   0.5  --                                  Glycerin  --        1.0    1.0  1.0  1.0  --                                  Methylparaben                                                                           0.1       --     --   --   --   --                                  Propylparaben                                                                            0.05     --     --   --   --   --                                  Polyethylene                                                                            1.0       --     --   --   --   --                                  Glycol E400                                                                   95% Alcohol                                                                             --        30     47.0 47.0 42.0 --                                  Water     52.05     63.5   46.5 47.5 46.5 100.0                               ______________________________________                                    

Composition A represents an embodiment of the present invention.Compositions B-E represent compositions of U.S. Pat. No. 4,511,486. Thecontrol formulation (F) was ordinary tap water.

Hydroxyapatite Dissolution Tests

Prior to testing the cleaning efficacy of the compositions on tartar andcalculus, a preliminary test was conducted to determine theeffectiveness of the compositions in dissolving hydroxyapatite (HA), acompound known to be a common type of calculus. To each of the abovesolution compositions was added powdered hydroxyapatite (HA), the knownmain ingredient found in tartar and calculus deposits. To 50 ml of theInventive Composition (A) was added 100 mg of HA. To 100 ml of each ofCompositions B-F was added 100 mg of HA. The concentration of HA in theInventive Compositions (A) was twice that of the prior art (B-F) toemphasize the greater ability of the Inventive Compositions atdissolving HA (calculus).

At the end of two hours of soaking the Inventive Compositions (A) hadcompletely dissolved the HA and the solution remained clear even afterone (1) week at room temperature. The prior art and control solutions,however, exhibited cloudy solutions after one (1) week of soaking,indicating failure of these compositions to dissolve the HA. CompositionB, which had the least amount of alcohol present relative tocompositions C-E, exhibited less cloudiness than the others.

Actual Denture Tests

At this point actual dentures were obtained, having visible buildup oftartar and calculus stain and deposits, from subjects. The dentures hadnot been exposed to any pretreatment whatsoever, nor were the subjectson any special oral hygiene program. The tartar and calculus stains anddeposits represented buildup occurring during ordinary usage andhygiene. Photographs of the dentures clearly indicated the buildup.

A denture was selected which was evenly stained with tartar and calculusdeposits on both the right and left sides. The denture was firstphotographed, then rinsed under running water and subjected to thefollowing regimen.

The left side of the denture was soaked in U.S. Pat. No. 4,511,486Composition B for four (4) hours at room temperature. The denture wasthe rinsed, air dried and photograhed. No visible stain difference wasdetectable between the side which was treated and untreated side,indicating that no significant removal of the tartar and calculusdeposits occurred.

The right side of the same denture was then soaked in the InventiveComposition (A) for one (1) hour at room temperature. The denture wasthen rinsed, air dried and photographed. The result was that no visibledetectable tartar or calculus deposit remained, indicating that thedeposits were removed from the denture.

The above experiments indicate the following:

(1) The inventive composition are able to dissolve hydroxyapatite, themain constituent in calculus and tartar, while the prior artcompositions of U.S. Pat. No. 4,511,486 are not.

(2) The inventive compositions are capable of removing stubborn calculusand tartar deposits and stain on dentures in one (1) hour of soaking,without brushing or other mechanical action. The compositions of U.S.Pat. No. 4,511,486 did not visibly show any removal of the deposits evenafter four (4) hours of soaking.

It is therefore evident, in view of this experiment that the inventivedenture spray compositions exhibit surprisingly superior results overU.S. Pat. No. 4,511,486.

EXAMPLE FOUR

The following compositions were prepared as a means of demonstratingsome of the various combinations possible within the ranges claimed.Those solutions which remained clear during storage are consideredpreferred embodiments since they remained free of precipitate and weretherefore easier to dispense through a spray nozzle. Additionally, thosesolutions which remained free of precipitate maintained the availabilityof the total detergent for cleaning. The balancing of amounts of theingredients within the preferred ranges such that adequate cleaning andsprayability exist, without excessive precipitate, is within the scopeof routine experimentation.

    ______________________________________                                        % by weight                                                                   Compo-                      Phos-            Clear/                           sition SLS    SDBS    EDTA  phonate                                                                              PEG  PG   ppt                              ______________________________________                                         1     15     --      18    --     --   --   ppt                               2     15     --      18    --     10   --   Slight                                                                        ppt                               3     5      --      10    --     --   --   ppt                               4     5      --      10    --     4    --   Clear                             5     5      --      10    --     6    --   Clear                             6     3      --      5     --     0    --   ppt                               7     10     --      5     --     4    --   Clear                             8     3      --      5     --     2    --   Clear                             9     3      --      3     --     0    --   Clear                            10     3      --      3     --     2    --   Clear                            11     15     --      18    --     --   0    ppt                              12     15     --      18    --     --   10   ppt                              13     5      --      10    --     --   0    ppt                              14     5      --      10    --     --   4    ppt                              15     5      --      10    --     --   6    ppt                              16     5      --      10    --     --   8    Clear                            17     3      --      5     --     --   0    ppt                              18     10     --      5     --     --   4    Clear                            19     3      --      5     --     --   2    Clear                            20     3      --      3     --     --   0    Clear                            21     3      --      3     --     --   2    Clear                            22     --     18      18    --     0    --   ppt                              23     --     18      18    --     10   --   ppt                              24     --     5       10    --     0    --   ppt                              25     --     5       10    --     4    --   ppt                              26     --     5       10    --     6    --   Clear                            27     --     3       5     --     0    --   ppt                              28     --     10      5     --     4.5  --   Clear                            29     --     3       5     --     2    --   Clear                            30     --     3       3     --     0    --   Slight                                                                        ppt                              31     --     3       3     --     2    --   Clear                            32     --     10      5     --     4    --   Clear                            33     --     18      18    --     0    --   ppt                              34     --     18      18    --     --   10   ppt                              35     --     5       10    --     --   0    ppt                              36     --     5       10    --     --   4    ppt                              37     --     5       10    --     --   6    Clear                            38     --     3       5     --     --   0    ppt                              39     --     10      5     --     --   4    Clear                            40     --     3       5     --     --   2    Clear                            41     --     3       3     --     --   0    Clear                            42     --     3       3     --     --   2    Clear                            43     --     15      --    16     0    --   ppt                              44     --     15      --    16     10   --   Light                                                                         ppt                              45     --     5       --    10     0    --   ppt                              46     --     5       --    10     4    --   Clear                            47     --     5       --    10     6    --   Clear                            48     --     5       --    10     8    --   Clear                            49     --     3       --    5      0    --   ppt                              50     --     10      --    5      4    --   Clear                            51     --     3       --    5      2    --   Clear                            52     --     3       --    3      0    --   ppt                              53     --     3       --    3      2    --   Clear                            54     --     15      --    16     --   0    ppt                              55     --     15      --    16     --   10   ppt                              56     --     5       --    10     --   0    ppt                              57     --     5       --    10     --   4    ppt                              58     --     5       --    10     --   6    ppt                              59     --     5       --    10     --   8    ppt                              60     --     3       --    5      --   0    ppt                              61     --     10      --    5      --   4    ppt                              62     --     3       --    5      --   2    ppt                              63     --     3       --    3      --   0    ppt                              64     --     3       --    3      --   2    ppt                              65     --     3       --    5      --   4    ppt                              66     --     3       --    5      --   6    ppt                              67     15     --      --    16     0    --   ppt                              68     15     --      --    16     10   --   ppt                              69     5      --      --    10     0    --   ppt                              70     5      --      --    10     4    --   ppt                              71     5      --      --    10     6    --   ppt                              72     5      --      --    10     8    --   ppt                              73     3      --      --    5      0    --   ppt                              74     10     --      --    5      4    --   ppt                              75     3      --      --    5      2    --   ppt                              76     3      --      --    3      0    --   ppt                              77     3      --      --    3      2    --   ppt                              78     3      --      --    3      6    --   ppt                              79     3      --      --    3      10   --   ppt                              80     1.5    --      --    1.5    5    --   ppt                              81     15     --      --    16     --   0    ppt                              82     15     --      --    16     --   10   ppt                              83     5      --      --    10     --   0    ppt                              84     5      --      --    10     --   4    ppt                              85     5      --      --    10     --   6    ppt                              86     5      --      --    10     --   8    ppt                              87     3      --      --    5      --   0    ppt                              88     10     --      --    5      --   4    ppt                              89     3      --      --    5      --   2    ppt                              90     3      --      --    3      --   0    ppt                              91     3      --      --    3      --   2    ppt                              92     3      --      --    3      --   6    ppt                              93     3      --      --    3      --   10   ppt                              94     1.5    --      --    1.5    --   5    ppt                              ______________________________________                                    

This invention may be embodied in other forms or carried out in otherways without departing from the spirit or essential characteristicsthereof. The present disclosure is therefore to be considered asillustrative and not restrictive, the scope of the invention beingindicated by the appended claims. All modifications which come withinthe meaning and range of equivalency are intended to be embraced herein.

What is claimed is:
 1. A storage stable liquid denture cleansercomposition consisting essentially of(a) a detergent present in amountsof about 3 to about 18% by weight selected from the group consisting ofsulfonate fatty alcohols having the formula ROSO₃ M, sulfated fattyalcohols having the formula ROSO₄ M, sulfoacetates having the formulaROCOCH₂ SO₃ M and mixtures thereof, wherein R is C₁₀₋₁₆, M is a watersoluble alkali metal or alkaline earth metal; and (b) a water-solublechelating agent present in amounts of about 3 to about 18% by weightselected from the group consisting of amino carboxylate, organophosphonates and mixtures thereof; and (c) water present in amounts ofabout 50 to about 94% by weight.
 2. The cleanser of claim 1 wherein thefatty alcohol detergent is selected from the group consisting ofpotassium lauryl sulfate, magnesium lauryl sulfate, sodium laurylsulfate, sodium cetyl sulfate, sodium tridecyl sulfate,sodium-7-ethyl-2-methyl-4-undecyl sulfate, sodium dodecylbenzenesulfonate, sodium lauryl sulfonacetate and mixtures thereof.
 3. Thecleanser of claim 1 wherein the chelating agent is selected from thegroup consisting of tetrasodium ethylenediaminetetraacetate dihydrate,trisodium ethylenediaminetetraacetate, diammoniumethylenediaminetetraacetate, sodium ethylenediaminetetraacetatedihydrate, trisodium N-hydroxyethylenediaminetriacetate hydrate,trisodium nitrilotriacetate monohydrate, pentasodiumdiethylenetriaminepentaacetate, trisodium ethylenediaminetetraacetatetrihydrate, the sodium salt of 1-hydroxy-1,1-diphosphonic acid, thepotassium salt of 1-hydroxy-1,1-disphosphonic acid, the amonium salt of1-hydroxy-1,1-disphosphonic acid and mixtures thereof.
 4. The cleanserof claim 1 wherein the cleanser is in sprayable form and wherein theratio of detergent to chelating agent is about 2:1 to about 1:1.
 5. Thecleanser of claim 1 wherein the chelator is present in amounts of about3% to about 8% by weight.
 6. The cleanser of claim 1 wherein thedetergent is present in amounts of about 3% to about 12%.
 7. Thecleanser of claim 1 wherein there is an additional anionic detergentselected from the group consisting of the oleic acid ester of sodiumisethionate, sodium N-cyclohexyl-N-palmitoyl taurate, sodium N-coconutacid-N-methyl taurate, sodium N-methyl-N-oleyl taurate, fluorochemicalsurfactants having the formula ##STR2## wherein n is an integer from 3to 10, X is bromine or iodine, and Y is a glycol residue having 3 to 10carbons and mixtures thereof.
 8. The cleanser of claim 1 wherein thereis additionally present a material selected from the group consisting offlavorings, colorings, perfumes, preservatives, builders, antimicrobialsand mixtures thereof.
 9. The cleanser of claim 8 wherein thepreservative is a paraben, the flavoring is mint and the builder isselected from the group consisting of water-soluble, phosphate,pyrophosphates, ortho phosphates, carbonates and mixtures thereof andthe coloring is an F.D. & C. or D. &. C. dye.
 10. The cleanser of claim1 wherein the cleanser is a soaking solution and wherein the ratio ofdetergent to chelating agent is about 1:4 to about 1:2.
 11. A method ofcleansing dentures comprising:(1) spraying the denture with a storagestable liquid denture spray composition consisting essentially of:(a) adetergent present in amounts of about 3 to about 18% by weight selectedfrom the group consisting of sulfonate fatty alcohols having the formulaROSO₃ M, sulfated fatty alcohols having the formula ROSO₄ M,sulfoacetates having the formula ROCOCH₂ SO₃ M and mixtures thereof,wherein R is C₁₀₋₁₆,M is a water soluble alkali metal or alkaline earthmetal; and (b) a water-soluble chelating agent present in amounts ofabout 3 to about 18% by weight selected from the group consisting ofamino carboxylates, organo phosphonates and mixtures thereof; and (c)water present in amounts of about 50 to about 94% of weight; and (2)rinsing the denture with water.
 12. The method of claim 11 wherein thespray has a force of at least one gram.
 13. The method of claim 11wherein the spray has a pattern with at least about 1.5" to about 2.5"when sprayed from a distance of about 2" from the denture.
 14. Themethod of claim 11 wherein the liquid denture composition is allowed toremain on the denture for about 20 to about 120 seconds prior to rinsingwith water.
 15. A storage stable liquid denture cleanser compositionconsisting essentially of:(a) a detergent present in amounts of about 3to about 18% by weight selected from the group consisting of sulfonatefatty alcohols having the formula ROSO₃ M, sulfated fatty alcoholshaving the formula ROSO₄ M, sulfoacetates having the formula ROCOCH₂ SO₃M and mixtures thereof, wherein R is C₁₀₋₁₆,M is a water soluble alkalimetal or alkaline earth metal; and (b) a water-soluble chelating agentpresent in amounts of about 3 to about 18% by weight selected from thegroup consisting of amino carboxylate, organo phosphonates and mixturesthereof; (c) water present in amounts of about 50 to about 94% byweight; and (d) a water-soluble, non-toxic glycol in an amountsufficient to prevent an insoluble precipitate from forming.
 16. Thecleanser of claim 15 wherein said glycol is a polyethylene glycol. 17.The cleanser of claim 16 wherein the polyethylene glycol is present inamounts of about 1 to about 10% by weight.
 18. The cleanser of claim 17wherein the polyethylene glycol has an average molecular weight of about200 to about
 600. 19. The cleanser of claim 15 wherein the cleanser isin sprayable form and wherein the ratio of detergent to chelating agentis about 2:1 to about 1:1.
 20. The cleanser of claim 15 wherein thecleanser is a soaking solution and wherein the ratio of detergent tochelating agent is about 1:4 to about 1:2.